A network of secret offshore deals and vast loans worth $2bn has laid a trail to Russia's president, Vladimir Putin. An unprecedented leak of documents shows how this money has made members of Putin's close circle fabulously wealthy.

Though the president's name does not appear in any of the records, the data reveals a pattern – his friends have earned millions from deals that seemingly could not have been secured without his patronage. The documents suggest Putin's family has benefited from this money – his friends' fortunes appear his to spend.

The files are part of an unprecedented leak of millions of papers from the database of Mossack Fonseca, the world's fourth biggest offshore law firm. They show how the rich and powerful are able to exploit secret offshore tax regimes in myriad ways.